We request funds for a confocal microscope with the capability to optically section and accomplish three-dimensional reconstructions. We will establish a joint facility that will primarily serve five laboratories in the Biology Department. The proposed instruments will be used to accomplish goals of funded NIH projects. All five laboratories are involved in studies of the structure and function of arthropod nervous systems. Current research uses molecular, genetic, biochemical, electrophysiological, behavioral and conventional anatomical technologies. The proposed instrumentation will extend the precision and resolution of ongoing work, and make possible experiments that are too time-consuming using existing instruments. Major research efforts involve molecular neurogenetic studies of Drosophila development, memory, courtship, and circadian rhythms. Also included are anatomical studies of the distribution of neuroactive molecules such as peptide neurotransmitters in Drosophila and in crustacean stomatogastric nervous systems. Subcellular localizations of proteins involved in RNA processing in yeast and Drosophila neurons are also intended.